This invention relates generally to color printing, and more specifically to printing different types of color objects in the same printout.
The use of color monitors for computers has accelerated the need for color printers which can produce a satisfactory printout of what is displayed on the screen. Part of the problem arises from the subjective nature of color. Color is a sensation produced by the combined effects of light, objects and human vision. A particular color or combination of colors may be appealing to one person while at the same time being offensive to another.
Another part of the problem arises from the different color technologies used in computer monitors and color printers. For example, computer monitors are based on a color gamut of red, green and blue pixels (RGB) while color printers such as inkjet printers are typically based on a color gamut of cyan, magenta, yellow and black (CMYK). The RGB color components of computer monitors are combined together in an "additive" way by mixing red, green and blue light rays to form a first variety of different colors, while the CMYK components of color inks are applied to media in different combinations in a "subtractive" way to form a second variety of different colors. A number of different color management techniques have been used on order to provide some form of matching between the colors viewed on a computer monitor and the colors printed by a specific printer using a given ink formula on a particular type of media. Such color management techniques have also employed different types of halftoning in order to improve the color output of printers.
Desktop publishing software programs have created additional problems by allowing different types of objects to be combined together into a composite document, such as photographic images, business graphics (e.g., charts), and scalable text in both color and black. By skewing the printer color output to ensure satisfactory color printing of photographic images, the business graphics in the same document often appear washed out and lose their impact. By skewing the printer color output to ensure satisfactory color printing of saturated vivid colors for business graphics, the photographic image in the same document loses its lifelike appearance.
Some of the aforementioned color printing problems have been partially solved by providing manually controlled printer settings to get the best results available. In addition, sophisticated users who demand exact color matching between screen and printout have obtained some solutions through color management software incorporated in the computer operating system as well as color management software incorporated into third party software applications. Also, some color matching technology has been incorporated into printer drivers which provide the translation interface between a particular computer and/or software application running in the computer and a color printer which acts as a hardcopy output device.
However, there is a need for better color management technology which allows for either automatic or customized settings respecting color correction as well as halftoning, and which allows different color schemes to be used for different types of objects such as photo images, business graphics, color text, and black text.